Michael -kennedy



@non (title,

Mic'nant KENNEDY,

OF NEW YORK, Y:

Letters Patent No. l113,529, dated April 1l, 1871.

IMPROVEMENT IN PLATFORM-SCALES.

The Schedule referred to in these Letters Patent and making part of chesame.

To all whom Ait may concern Be it known that I, MICHAEL KENNEDY, of thecit-y, county, and State of New York, have invented certain new anduseful Improvements in Platform- Scales; and I do hereby declare thatthe following is a full, clear, and exact description thereof, referencebeing had to the accompanying drawings making part of thisspecification, in which- Figure l is a top view with theplat-formremoved;

Figure 2, a vertical section taken in the plane of the line x" x of fig.l;

Figure 3, a section taken in a vertical plane passing through the middleof one pair of primary levers and Figure 4, a frontl elevation and asection of one of the primary levers, bearings, and connections on anenlarged scale.

` The same letters indicate like parts in all the figures. v

My said invention relates to 1m provements in what are known as theSampson scales.

Therst of my said in'iprvements relates to means for reducing thefriction of the levers that vibrate in horizontal or inclined planes,which improvement cousists in forming a pivot in lline with theknife-edge fnlcrum of suchv levers to rest on a steel bearing be-'low,`so that the friction (lue to the weight of such levers whenvibrating shall n ot materially impede the Working. The bell-cranklevers' of such scales are usually made of cast-iron, and theknife-edges of steel set into the cast-iron, and, as heretofore made,the slightest lateral play causes the bearing-blocks to make frictionagainst the sides of the levers. lVith a view to reduce such friction-`rlhe second part of my said invention consists in having'the steelknife-edges formed with end-shonl ders projecting from the surface ofthe cast metal, and the bearing-blocks with lateral steel points inline, as near as may be, with the knife-edge, so that, incase of 'anylateral movement, the saidv steel points shall come int-o contact withthe shoulders of the knife edges and thus avoid the greater part of thefriction whichotherwise would impede the free working of the saidlevers; and

rlhe third part of my said invention relates to the adjustability ofthe-knife-edgc in one arm of the bellcrank. levers.

I am aware that such knife-edge has heretofore been made adjustabletoward and from the fnlerum of the lever; but my said improvementconsists in combining with the slide to which the knife-edge is secured,and the adjusting-screw by which the slide is moved, cheeks, whichembrace the sides of the arm of the lever, or as the equivalent thereof,which are embraced by the sides of the arm of the lever, so that freeaction of the scale.

the parallelism of the knife-edge and the fulcrum of the lever shall bemaintained.

Then the lever which serves to transmit the action of the platformdirectly or indirectly to the beam is placed between the secondarylevers, one of them must transmit such action by thrust; and if theconnection be formed by a solid rod it is liable to yield by ilexure,unless it be made so thick as to be an objectionable weight.

The fourth part of my said invention consists in combining with thesecondary levers and the transmitting-levers, placed between them, theconnection of the lever so interposed with that one of the sec ondarylevers which imparts the act-ion oy thrust, a tubular comiecting-rod, orthe equivale-ut thereof, whereby the lexure is avoided without too muchweight.

y ln platformescales the short arms of the primary levers, on which theplatform rests, are nnavoidably in a horizontal, or nearly horizontal,position; and the practice has been to make such arms solid, so thatwater, dust, and other impurities accumulate on the upper surface andcannot escape, and, in consequence, the knife-edges soon become rust-yand impede the \Vith a view to remedy this defect- The last part of mysaid invention consists in constructing the lower arms of the saidprimary levers with an open space between the knife-edges on which theplatform rests and the fulcrum, for the free escape of water and dirt.

In the accompanying drawingsa represents the usual frame-work of aplatformscale, such as used for railroads, and

b b the lower timbers, on which arc secured the bearings c c c c for theprimary levers d l d el, two on each side.

The said bearings c c c c are formed each of a baseplate and twostandards, preferably made of cast-iron, to the upper end of whichstandards are litt-ed steel bearings, on which the knife-edge fulcrumsof the levers rest and vibrate.

The inner faces of these steel bearings are beveled to a point, so thatthc most projecting part shall, as near as possible, be in line with theknife-edge of the fulcrum of the primary levers when iu place, `theobject of this construction having been stated in declaring the natureof my invention.

The primary levers d are all alike, and preferably cast in one piece.The description of one will do for all.

cross-pieces, f y It.

The fulcrum 'i is made of steel and embedded in the cross-piece f, andprojects on each side of the side It consists of two side pieces, e c,connected by three pieces to a suftlcient distance to rest on thebearings c c, the under surface ot the projecting parts being brought toa knife-edge.

The side pieces e 'c vare formed lwith projecting shoulders, j j,extending out as far as the fulcrum, to

vgive ample support.

. Ou each side of the lever the steel fulorum is formed with a shoulder,lt, slightly projecting from the outer faces of the lever and next tothe inner Vends ot' the knife-edges, so that, in case oi'any lateralplay of the levers when in action, the said steel shoulders shall comein contact with the projection on the outer faces of the steel bearings,and thus reduce to the minimum 'the i'riction due toany contact whichmay take place-` `when the levers are in action.

The lower and short arm of the primary levers is provided with a steelknife-edge, Z, embedded in the cross-piece y, and this is formed withend shoulders projecting from the inner faces of the side pieces vot'the lever; andthe middle of the balance-bar m, which rests on thisknife-edge, is made ot' steel, with the e`nds beveled to points, inlikel manner and for the same purpose as the steel bearings for thefulcrum before described.v

'lhere is one such balance-bar m for each of the primary levers, theends of each balancebar being connected by snspensionlinks n n, withhangers o o oft-heplattbrm p, as'in scales heretofore used.

The upper and long arm of the primary levers is formed with the twosides beyond the third crosspiece il, parallel, to form ways, to whichis fitted a slide, g, with side checks o' o* embracing, so that the saidslide shall not have lateral play.

rlhe steel knife-edge s for this arm of the lever is embedded in across-piece of the slide q, and formed with end shoulders, in likemanner and for thesame purpose 'as the knileedges before described.

The slide q is provided with an adj listing-screw, t, which extendsthrough a hole in the betbre-named third cross-piece h of the lever, sothat, by means or" nuts on each side ot' the cross-piece, the distanceot the kuife-edge s can be adjusted relatively to the t`ul`- f orum withthe greatest nicetyand there secured. The.

cheeks t' fr'that embrace the ways eiieetually-maintain the parallelismot' the knife-edges.

The primary levers are connected in pairs by two rods, a u., one on eachside, Vthe ends of the said connectingrods being provided with steelbearing-blocks o o, the sides of which are beveled to points to reduce.friction, in connection with the shoulders at the ends of theknite-edges'.

The lower arm of the primary levers is formed with an open space, w,between the fulcrum, and knifeedgc l, for the tree passage or" water anddirt, which otherwise would accumulate on that part ot' the lever andsoou'impede the free action of the parts, as in scales heretofore made,

The two pairs oi' primar7 levers are connected with the secondary leversx 1', one ou each side, by means of two auxiliary rods, y y, connectedwith the rods n et, before described.

These secondary levers are constructed in manner similar to the primarylevers, and the auxiliary connectiug-r0ds y y; are connected with theirshort arms, the knife-edges being formed with end shoulders, and thesteel bearing-blocks in the rods with the sides beveled. to points, asbefore described, in connection with the primary levers.

These Vsaid secondary levers vibrate in horizontal planer, and thebearings c z for their fuicrums are secured to and project from a beam,c', of the frame; and to reduce the friction which would be induced bytheir entire weight when in action, the lower end et' the fulcrnzuot'eaeh lever is brought to a point in line with the knife-edge, andthis point rests on a hardened steel plate, b', secured to a stud, c'.

'lhe knife-edges of the longer arms of these levers are mounted inadjustalrle slides, similar to those on the upper arms of the primarylevers.

rlhe two secondary levers are connected with one intermediate lever',al', which also vibratcs in a horizontal plane, the knife-edges ot' itsfulcrnrn working against bearings c, secured to and projecting from abeam, f', of the frame, the friction due to the weight ot' this 'leverbeing reduced in the same. manner as described in reference to thesecondary levers. The knife-edge on one of the arms of this lever isalso adjustable in manner similarto the levers before described.

As this lever is placed between, and receives motion simultaneouslyfrom, the two secondary levers, one must pushand the other pull; and ifboth were connected by rods, one ot' them, unless made of too great aweight, would yield by tlexure.

To prevent this the connection on one side is formed` by a rod, g', andon the other by a tube, h'.-

The tube It is provided with bcariilgddocks at each end, and one end ofthe tube is connected by an open link, c", with the rod y.

The bearing-block at that cud of the tube Vnext to the secondary leveris mount-ed in a piece separate from, but fitted to, the end ofthe tubeby a threaded socket, to admit of adjusting the length.

rlhe intermediate lever last des lribed is in turn connected by a rod orlink, j', with the short arm ot' a transinitting-lever, It', the longarm oi' which is in turn connected by a link, I, with thc steelyard mi',the kniteedge in the long arm of the said ltransmittinglever beingmounted in an adjusting-slide, and the liilcruiu and kniteedgcs andbearing-blocks being iorzned and connected in like manner as t-heprimary and secondary levers, before described.

And although 'I prel'er a tube for forming the connection between theintermediate lever and that one of the secondary ievers which acts bythrust, as best suited to prevent ilexure, l do not wish te beunderstood as limiting my claim of invention to that form. as a thin rodwith three or more projecting flanges, or three or more thin rodsconnected by end plates, will answer the same purpose.

All the fulcruins and knife-edges, with their end shoulders, and thebearings with beveled or pointed faces, are to be made ot' steel,properly hardened, or ol' equivalent hard substance..

\Vhat l cla-im as my invention, and desire to secure by Letters Patent,is

l. In combination with a lever which vibratcs in a horizontal orinclined plane, and whose axis of vibrat-ion is a knife-edge,substantially as described, a point or pivot at the lower end of itsfnlcrum and in line with the kniteedge, and a bearing 'or the. saidpoint or pivot, substantially as and' for the purpose de scribed.

2. rlhe knife-edges formed with end shoulders, in combination with thesides or ends of the bearingblocks beveled to a point, or nearly as mayhe in line with the knii'e, substantially and for the purpose described.I

In combination with the secondary levers and a transmitting-leverinterposed between and receiving action from both simultaneously, acomiecting-lube, or the equivalent thereof, tor transmitting the actionby thrust, substantially as and for tlc purpose described.

